2002 XC: studded and stalls (sometimes)

[carboncow]

Helping neighbor kid with his 2002 XC70, almost 200K miles. I've seen these symptoms before an first I thought it was a misfire so I had him put new plugs in and we may clean the MAF tomorrow. After new plugs were in it seems the same (no better) and we put Vida Dice on it. although there are a few issue he's always had with a minor evap leak and a VVT valve we now are seeing turbo sensors and a waste gate issue along with MORE evap errors.

Car runs fine once it pulls aways but sometimes stalls on a decal when at the stop sign, but not always. Then when you go to give gas there is a small hesitation that almost wants to make it fail but then recovers quickly and drives fine all up to highway cruising speed. We've even noted he gets better gas mileage then me (approx. 26mpg) under this condition!

Worth noting the following...

1. Found no vac leaks anywhere. I hear nothing and I inspected most lines I know
2. We swapped out a known good (used) TCV from my 2003 XC70. I know I replaced those in almost every P2 I've ever owned.

I'm included two screenshots from the car. The first one (with fewer errors) is after a "clear all" and the car sitting with the ignition switch on by the car has NOT run yet. So these errors are coming up prior to running and you will see mention of obvious things that can trigger w/o running such as the PDM and CCM. With the two showing ECM (boost pressure sensor (single to low) as well as the VVT valve (signal to low) are these telling me there is an issue with the wiring as it's throwing a code prior to even running?

The 2nd screenshot is off all the errors after the car has been started and rev'd to 2000+ RPM.

What do you think is at work here?

A turbo signal, waste gate issue aand/or evap issues?
What is this ECM-1600 Boost Pressure Sensor it speaks of, is this the TCV? If so do we have a bad wire he we put a known good one on?

NOTE: The kid was away for a week to travel and his brother used the car...not sure what he could have done hot rodding it or not, but a variable of "little brother" to consider!

Thanks all.